impact melt

Rock that has been made temporarily molten as a result of the energy released
by the impact of a large colliding body. Impact melts include small particles,
known as impact melt spherules, that are splashed out of
the impact crater, and larger pools and
sheets of melt that coalesce in low areas within the crater. They are composed
predominantly of the target rocks, but can contain a small but measurable
amount of the impactor.